An integrated controller of wind turbines with both inertial response and primary frequency regulation (PFR) to provide complete dynamic frequency support for the grid with high wind power ...penetration is investigated. The wind turbine control governor contains two cross-coupled controllers: pitch controller and maximum power point tracking (MPPT) controller. First, as a precondition for the PFR, a de-loading pitch control scheme is proposed to reserve capacity required for frequency regulation. Then, by optimizing the MPPT scheme, the rapid virtual inertia response is achieved even under de-loading operation condition. Based on the analysis of the steady-state characteristics of wind turbines with frequency droop control, the primary frequency control strategy, which enables the adjustment of frequency droop coefficient, is further proposed through pitch angle changes. Thus, the PFR and inertial response can be both achieved by the proposed de-loading pitch controller and optimized MPPT controller. A three-machine prototype system containing two synchronous generators and a Doubly Fed Induction Generator (DFIG)-based wind turbine with 30% of wind penetration is implemented to validate the proposed integrated control strategies on providing inertial response and subsequent load sharing in the event of frequency change.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Voltage feedback flux-weakening control has the advantages of simplicity and robustness against parameter variation. However, due to less voltage control margin in the flux-weakening region, the ...increased feedback voltage ripple could deteriorate the system performance in the flux-weakening region and may even cause oscillation. In this article, based on a nonsalient permanent magnet synchronous machine, the steady-state feedback voltage ripple in the flux-weakening region are analyzed first. It shows that the feedback voltage ripple caused by the current command ripple could dominate in some flux-weakening regions. Consequently, the speed bandwidth based on the conventional speed proportional-integral (PI) controller in the flux-weakening region can be hardly increased, which leads to poor dynamic performance. In order to obtain both fast speed dynamics and less steady-state ripple, especially in the flux-weakening region, an adaptive fuzzy logic (FLC) speed controller is designed and compared with the conventional speed PI controller. With the adaptive FLC, the dc-link voltage utilization can be increased and better flux-weakening capability can be obtained. Finally, the improved performances are verified by the experimental results.
This paper presents the multi-loop digital controller design of a quasi-z-source inverter (qZSI). The qZSI is a single-stage power converter and can operate in buck and boost modes. The qZSI is an ...economical solution for distributed generation and eliminates the need for two-stage power conversion. This paper proposes a detailed step-wise digital controller design using a multi-loop control method. The controllers of the AC and DC sides are designed separately. A proportional controller is used for the inner current control loop on both the AC and DC sides. In contrast, for outer voltage loop control, the proportional and resonant (PR) controller is used on the AC side, and the proportional and integral (PI) is used on the DC side. In designing the digital controllers, the effect of the sensor gain and low pass filter (LPF) in the feedback path is also considered. Furthermore, to mimic the behavior of the synchronous generator, the droop control is used to generate the reference voltage for the AC side of the controller. The time domain simulations are carried out to verify the designed controllers. Experimental results are also presented for the validation of the proposed controllers.
The modern power system (PS) is an intricate manmade control system. Automatic generation control (AGC) executes an imperative contribution in PS operation to preserve its frequency and tieline power ...flow within a tolerable range following continuously varying load demands. Hence, a wholesome and expert controller for AGC is obligatory to deliver superior power to the end users. The objective of this article is to design a cascaded fuzzy fractional order (FO) PI-FOPID (CFFOPI–FOPID) controller as a novel control strategy for AGC problem solution in electric PS. The controller parameters are determined employing a recent stochastic imperialist competitive algorithm. The controller assures the convergence of deviation in area frequency and tieline power under load disturbances to zero in minimum definite time. Single and interconnected multi-area thermal PS models are utilized as test systems to authorize the efficacy of the method. Results analysis reveals the advantage of CFFOPI–FOPID controller over various prevalent controllers. The models are also explored with appropriate generation rate constraint. Robustness test validates controller’s robustness at large changes in system parameters, random change in power demand and additional imperative nonlinearities.
•A new CFFOPI–FOPID controller is presented for AGC of power systems.•Optimal parameters of the controller are acquired adopting ICA.•Isolated and interconnected power systems are simulated to show the effectiveness of the controller.•The supremacy of the controller in established over various existing controllers.•Robustness of the controller is verified via robustness analysis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Modern vehicles are no longer considered as mere mechanical-based device, instead, they have been hugely replaced by sophisticated electric devices known as Electronic Control Unit (ECU). These ECUs ...are communicating with each other by publishing/receiving messages that complies with well-known protocol called Control Area Network (CAN). CAN bus is responsible to ensure all critical parts in vehicle e.g. engine, braking, airbag deployment, steering wheel, acceleration, etc. are functioning properly. This indicates that CAN bus is considered as the back-bone network protocol in modern vehicles. Unfortunately, the CAN bus protocol is vulnerable to various cyberattacks due to the lack of security mechanism in the protocol which has introduced several attack surfaces and allows attackers to have legitimate access to the bus and launch malicious activities. This paper proposes a new effective security solution that can detect three different types of message injected attacks namely Denial of Service (DoS), fuzzy, and impersonation attacks in the CAN traffic based on deep learning model. Moreover, the proposed method makes the use of evolutionary optimization algorithm to avoid premature convergence and manual selection of deep learning network architecture. To assess the practicality and effectiveness of the proposed method, CAN traffic is logged using unmodified license vehicle. Furthermore, the proposed method is evaluated using two other different CAN traffic dataset that proves the proposed method can be applied for different car make and models.
This study presents a novel adaptive management strategy for power flow in standalone hybrid power systems. The method introduces an on-line energy management by using a hierarchical controller ...between three energy sources: photovoltaic (PV) panels, battery storage and proton exchange membrane fuel cell. The proposed method includes a feed-forward, back-propagation neural network controller in the first layer, which is added in order to achieve the maximum power point for the different types of PV panels. In the second layer, a fuzzy logic controller has been developed to optimise performance by distributing the power inside the hybrid system and by managing the charge and discharge of the current flow. Finally, and in the third layer, local controllers are presented to regulate the fuel cell/battery set points in order to reach to best performance. Moreover, perturb and observe algorithm with two different controller techniques – the linear proportional-integral (PI) and the non-linear passivity-based controller – are provided for a comparison with the proposed maximum power point tracking controller system. The comparison revealed the robustness of the proposed PV control system for solar irradiance and load resistance changes. Real-time measured parameters and practical load profiles are used as inputs for the developed management system. The proposed model and its control strategy offer a proper tool for optimising the hybrid power system performance, such as the one used in smart-house applications.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This research study presents the fuzzy space vector pulse width modulation (FSVPWM) method of current control for three-phase voltage source inverter. The hybrid fuzzy particle swarm ...optimisation-based maximum power point (MPP) tracking algorithm has been employed to obtain high tracking efficiency as well as optimal MPP under adverse operating states. The FSVPWM technique provides less current harmonic content, fixed switching pattern, protection from over current, low switching losses and able to handle the non-linearities and uncertainties of the photovoltaic-wind grid integrated system. Grid synchronisation with sinusoidal current injection is achieved using the inverter controller. Fuzzy logic controller-based SVPWM controller compensates current error and provides DC-link utilisation with high efficiency. The experimental responses have been validated using MATLAB/Simulink interfaced real-time dSPACE DS 1104 controller. Irrespective of solar irradiance and wind velocity, the proposed hybrid system obeys MPP accurately with high performance.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Ships are highly vulnerable to external disturbances like sea waves and sea winds; its course keeping is a core problem of ship motion control. In order to solve the problems of ship heading control ...a better rudder action is needed to control the ship motion. In this research study, variable structure based nonlinear control algorithms namely integral sliding mode, double integral sliding mode, terminal sliding mode and supertwisting sliding mode controllers have been proposed to provide the robust solution against external disturbances. Lyapunov stability theory has been considered to check the asymptotic stability of the system. Smoothness, energy consumption and output response performances have also been calculated to further validate the performance of suggested controllers. Robustness of all the suggested controllers have been validated by adding the disturbance effect into system model. Particle swarm optimization approach has been used to get the optimal performance of better performing controller by tuning its gains. Furthermore, suggested nonlinear controllers have been simulated in MATLAB/Simulink and their comparative analysis has been showed with each other and with the literature’s developed nonlinear controllers. To further ensure the superiority of best performing proposed controller, a real-time controller hardware in the loop experimental test has also been presented.
•A dynamical ship model has been considered and variable structure based controllers have been proposed for automation of ship heading.•Asymptotic stability using Lyapunov Stability Theory has been proved.•A particle Swarm optimization algorithm is used to tune the gains of controllers to achieve optimal performance of controllers.•Comparative analysis of proposed nonlinear controllers with each other’s and with the proposed controllers in the literature has been presented.•A real-time controller hardware in the loop (CHIL) experimental test has also been presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this study, an adaptive controller is proposed for shunt active power filter (SAPF) to improve the harmonic compensation performance. The proposed controller forces the source current to become ...sinusoidal, with less total harmonic distortion and also maintained in phase with the supply voltage. The merits of modified adaptive controller over existing controller are verified in terms of harmonic compensation ratio factor for various perturbations of load and filter parameters. The eficacy of the proposed indirect current control with model reference adaptive controller (ICC-MRAC) control approach is tested by comparing the existing indirect current control with propertional–integral controller (ICC-PI) with the ICC-MRAC algorithm and then justified through laboratory prototype studies followed by using dSPACE 1104. It is observed from the result of implementation that the proposed controller-based SAPF performs superior than the existing ICC-PI in terms of robustness, adaptability, reliability and flexibility to various grid perturbations, such as harmonics, noise etc. Thus, the improvement occurs in power quality is due to the perfect harmonic rejection from current.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The existence of a generalized interline power-flow controller (GIPFC) in the transmission lines changes the voltage and current signals which are measured with the protection relays of power system ...dynamically. In this paper, the effects of the GIPFC on the measured impedance by the loss of excitation (LOE) relay of the synchronous generator are first investigated by analytical and computational methods for different operating modes of the power system. The results indicate that the presence of GIPFC causes a substantial delay on the operation of the LOE relay. It is also shown that when partial LOE occurs, the GIPFC causes to the LOE relay under-reaching. Consequently, to readjust the relay in the presence of the GIPFC, a new modified LOE protection algorithm on the basis of synchronized phasor measurements received from phasor measurement units is presented. The most important advantage of this modified algorithm is that it is a general algorithm which considers all voltage-source-converter-based flexible ac transmission systems controllers. Regarding the simulations results, it is concluded that using the modified algorithm for the LOE relay can sufficiently decrease the delay and prevent the relay from under-reaching. The impacts of the unified power-flow controller and interline power-flow controller on the LOE relay are also demonstrated.
